Tubular carton with strong end closures



Dec. 27, 1949 Rl GLER 2,492,712

TUBULAR CARTON WITH STRONG END CLOSURBS Filed July 3, 1946 IN VEN TOR.

ATTORNEYS.

Patented Dec- 27, 1949 TUBULAR CARTON WITH STRONG END GLOSUBES William A. Rlngler, Wayne, Pa., assignor to The Gardner Board and Carton 00., a corporation of Ohio Application July 3, 1946. Serial No. 881,340

4 Claims. (Cl 229-39) 1 My invention relates to the provision of cartons of the knocked-down, tubular type, which are provided with strong end closures. Such cartons have many uses; but as an exemplary field of utility presenting a number of problems which this invention successfully solves, I mention the use of my cartons as mailing boxes for articles of merchandise, in which field they take the place of the hitherto current set-up boxes with bendable wire fastening means.

It is an object of the invention to provide a closure which is exceptionally strong, contributing strength and rigidity to the entire structure.

It is an object of my invention to provide a type of closure which is easily and simply eflected, involving only folding and tucking operations, and in which the intereugagement of parts is substantially automatic in character.

It is an object of my invention to provide a type of closure which is not subject to accidental 2 cross-section. The side edges of the flaps 8 and 'I are articulatedwwebs l, 2, l2, and H which are also articulated to the ends of the body walls I andilyingoneachsideofthebodywallsl The webs are provided with diagonal score lines l2, l3, fl and II.

The closure flaps 8 and 'I are, in general dimensions, of a size substantially to cover the opening, either because of the strains of handling, or by catching on external. objects, or because of the weight of the contents of the box. Yet it is an object of the invention to provide a closure which may readily be opened when desired, and as readily reclosed, without loss of the strength and security of the package. These and other objects of the invention which will be set forth hereinafter or will be apparent to one skilled in the art upon reading these specifications I accomplish by that construction and arrangement of parts of which I shall now describe an exemplary embodiment. Reference is made to the drawings forming a part hereof, and in which:

Figurelisaplanviewofablankformy exemplary carton.

Figure 2 is a plan view showing the carton blank in tubed condition.

Figures 3 to 6 inclusive are partial perspective views showing the various steps of erecting the end closure, and a closed carton made in accordance with my invention.

The invention herein described will be understood to be applicable to cartons having wide variations in shape and size. 1

In the blank for the exemplary structure I have indicated a plurality of body walls I, 2, 2 and l in articulation on the usual score lines, together with a glue flap 5 articulated to a side edge of one of the body walls. Closure flaps 8 and I are articulatedrto the ends of one of the body walls, which will be one of the wider walls ofthecartonifthecarton'isofotherthansquare entire ends of the box; but the free edges of these flaps are cut back as shown to provide tabs l6 and I! in their midsections. It is not necessary that these tabs be formed in the centers of flaps 8 and I, but the outer edges of the tab should be inset somewhat at least from the outer edges of the naps. The tabs are less in width than the width of the flaps, and the bases of the tabs may be connected with the outer edges of the flaps t and 1 adjacent their corners by curved or substantially diagonal lines of cut as will be clear from the various fl m'w.

Where the carton is of the particular proportions shown in Figures 1 and 2. it may be neces-. sary to notch the webs I, 2', II, and II as shown at ll, I9, and 2|. The notching is so accomplished that the width oi the portion A indicated in Figure l is substantially half the width of the body wall 2. In cartons of other proportions no notching is necessary. Instead of notching, where the bellows folds are eflectively longer than the distance between end walls of the carton, I may merely cut back the ends of the bellows folds.

The body wall 4 is provided with articulated closure flaps 22 and 23 which are free of attachment to the webs. These flaps are provided with lines of cut forming slits 24 and 25 of shallow U-shaped configuration, de-marking tabs 24a and 25a; and the ends of these slits are connected with the side edges of the tabs 22 .and 23 by score lines 25 and 21. The position of these score lines is such that in the closed carton they will lie substantially along a prolongation of the bases of the tabs It and II.

The essentials of the blank for my carton have been described above. The carton may be modified in known ways to give it additional characteristics and utility. For example, one of the walls may be provided with a window opening 28 covered by a-sheet of transparent or translucent material 22.

The carton blank of Figure 1 may be tubed in the usual fashion on the usual carton folding and gluing machines. This may be accomplished by folding the blanks on the lines of articulation between body walls I and 2 and body walls I and 4, accompanied by the adhesive union of the gluev anon-:12

flap I with the free marginal portion of the body wall I. as is well understood in the art. The resuit is the tubular structure illustrated in Figure 2. It is in knocked-down or collapsed condition. and is in the form in which the structures will be shipped from the box manufacturer to the box user.

In use, the tubular body of the box is erected or squared up in the usual fashion, preparatory to eifecting the end closures. The closing of one end is illustrated in Figures 3 to 6 inclusive, but the same operations will be performed upon the other end. The erected carton is shown in Figure 3 with the closure flap :2 bent slightly out of the way. The next operation will be an inward folding of the flap t, accompanied by the inward bellows folding of the webs O and II along the score lines I I and I5. This is readily accomplished by pressing inwardly on the webs.

and at the same time initiating the folding of the flap 6.

In the particular carton of proportions shown in Figures 1 and 2 the result of the folding operation will be to cause the angular projections of the web to cross each other; and if the flap 6 be folded all the way in. as shown in Figure 5, the side edges of the notches or cut outs II and II will come substantially together at the midsection of the end closure. The flap i and the adjacent portions of the bellows folds form a pocket to receive the closure flap 22. This flap should be bent along the score line 2 and its end inserted in the pocket aforesaid. It is easiest to do this before the flap 6 has been folded all the way in. When the end of flap 22 has been engaged in the pocket the folding of flaps i and 22 may proceed concurrently until the completed closure is formed as shown in Figure 6.

It will be noted in Figures 4 and 5 that when the end portion of figure 22 is bent over, the tab formed by the out line 2| remains in the plane of the remainder of flap 22. As the folding progresses, the tab l6 comes beneath the tab 24a so that the tab II passes automatically through the slit 24; In the final closure the tab 24a overlies the flap 6, but the remainder of the flap 22 lies essentially beneath the plane of the flap 6. The flap 22 straightens out again during the folding, and thus there is formed a tight and secure frictional engagement of the flaps not liable to accidental dislodgement.

It will be noted from Figure 6 that my closure presents only folded paper board portions at the end edges of the body walls. The construction is such as to present no projections of a type liable to catch on surrounding objects. The interengagement of the flaps is frictionally very tight, and the closure is both strong and secure.

The result of the tight frictional engagement of the flaps and parts thereof, including the tabs Ii and 24a, is to rigidify the end of the box, thus contributing very greatly to the strength of the structure.

Nevertheless, by engaging the tab 24a deliberately and pulling outwardly and upwardly, which will result in a flexing of the tab 22, it is possible to reopen my carton with ease, and without disruption of any of its parts. By a repetition of the closure operations hereinabove described the carton may be reclosed with a closure of equal sepurity.

Modifications may be made in my invention 4 without departing from the spirit of it. Having thus described my invention in an exemplary embodiment, what I claim as new and desire to secure by Letters Patent is:

l. A tubular carton having enclosing body walls in articulation, and closure means articulated to the ends of the body walls, one of the said closure means being a flap articulated to one of the body walls and of general dimensions to cover the end of the carton, the closure means articulated to adjacent body walls being diagonally scored webs articulated also'to the side edges of said flap, a body wall opposite to the first mentioned body wall having closure means in the form of a flap also of general dimensions to cover the end of the body wall, the outer portion of said first mentioned flap being cut back to form a tab, with the base of said tab connected to the outer corners of said first mentioned flap by lines of cut, said last mentioned flap having an intermediate transverse slit, said first mentioned flap and said webs being foldable inwardly to form a pocket to receive and frictionally engage said last mentioned flap, with said tab through said slit.

2. The structure claimed in claim 1 wherein said slit is of shallow U-shape demarking a tab extending away from the last mentioned body wall, the ends of the slit being connected by score lines to the side edges of said last mentioned flap, whereby when said flap is flexed and inserted in said pocket, said last mentioned tab extends so as to cause said first mentioned tab to pass through said slit automatically.

3. The structure claimed in claim 1 in which said first and last mentioned body walls are wider than the remainder of said body walls, and in which said webs are notched, providing portions with edges coming together in the midsection of the carton end when the closure is eifected, and underlying portions in lapping relationship.

4. The structure claimed in claim 1 in which said first and last mentioned body walls are wider than the remainder of said body walls, and in which said webs are notched, providing portions with edges coming together in the midsection of the carton end when the closure is effected, and underlying portions in lapping relationship and wherein said slit is of shallow U- shape demarking a tab extending away from the last mentioned body wall, the ends of the slit being connected by score lines to the side edges of said last mentioned flap, whereby when said flap is flexed and inserted in said pocket, said last mentioned tab extends so as to cause said first mentioned tab to pass through said slit automatically.

extending inwardly WILLIAM A. RINGIER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 460,817 Clark Oct. 6, 1891 1,669,454 Close May 15, 1928 1,767,734 Brown June 24, 1930 2,216,527 Weiss et a1 Oct. 1, 1940 2,297,571 Lowey Sept. 29,1942 2,337,198 Holy Dec. 21, 1943 

